In recent years, ceramic filters have been used in order to selectively collect only specific components from a multicomponent mixture (mixed fluid). The ceramic filters are excellent in mechanical strength, durability, corrosion resistance, and the like as compared with organic polymer filters, and thus preferably applied to water treatment and exhaust gas treatment, or to the removal of suspended matters, bacteria, dust, and the like in liquids and gases in a wide range of fields such as medicinal and food fields.
Ceramic porous bodies with zeolite membranes formed thereon are known as such filters.
Zeolite is known to adsorb water molecules in its pores, and when the zeolite membranes are used as separation membranes, there is concern that water molecules may block the pores and decrease the permeation amount.
Known are: a method of draining the inside of pores by heating zeolite powders or particles (Patent Document 1); a regeneration method of removing a protective membrane coated on a zeolite separation layer (Patent Document 2); a method of immersion in water (Patent Document 3), and the like.